DMPP-2 b
Astrophysical Synthesis & Habitability Characterization
DMPP-2 b is a confirmed gas giant exoplanet orbiting the star DMPP-2, located approximately 449.9 light-years (137.94 parsecs) from the Solar System. First announced in 2019 by Multiple Facilities using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 14.2 Earth radii (1.27 Jupiter radii) and has a measured mass of 171.48 Earth masses (0.54 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.33 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.85 g⊕ (8.34 m/s²), and an escape velocity of 38.9 km/s.
In its orbital architecture around DMPP-2, DMPP-2 b completes one full revolution every 5.203 Earth days at a semi-major axis of 0.06638 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 138.8 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.06 carries the world between 0.0624 AU at periapsis and 0.0704 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1000 K (+727°C / +1341°F) and receiving 288.22 S⊕ (~392,272 W/m²), DMPP-2 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star DMPP-2 is classified as a warm F-type star of spectral type F5 V with an effective photospheric temperature of 6,500 K, a radius of 1.78 R☉, a mass of 1.41 M☉, an estimated bolometric luminosity of 5.074 L☉. Stellar evolution modeling indicates an estimated stellar age of 2 Gyr. From Earth, DMPP-2 shines at apparent V-band magnitude 8.57 (accessible to binoculars and small amateur telescopes) in the Southern celestial hemisphere. The DMPP-2 system is a multi-planet architecture hosting 3 confirmed worlds, with DMPP-2 b sharing its stellar neighborhood alongside DMPP-2 c, DMPP-2 d.
Methodology: Computed using the Schulze-Makuch et al. (2011) weighted metric comparing physical interior (radius, estimated density) and surface thermal regime (escape velocity, equilibrium temperature).
Discovery Facility: Multiple Facilities · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | DMPP-2 |
| Spectral Type | F5 V |
| Effective Temp (Teff) | 6,500 K |
| Stellar Radius | 1.7800 R☉ |
| Stellar Mass | 1.4100 M☉ |
| Bolometric Luminosity | 5.074 L☉ |
| Metallicity [Fe/H] | — |
| Stellar Age | 2.000 Gyr |
| Apparent Magnitude | V: 8.570 · G: 8.458 |
| System Architecture | 1 Star, 3 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.066380 AU |
| Orbital Period | 5.203 days |
| Mean Orbital Velocity | 138.8 km/s |
| Orbital Eccentricity (e) | 0.06000 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 0.33 g/cm³ (38.9 km/s vesc) |
| Insolation Flux | 288.2234 S⊕ (~392,272 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 449.900 LY (137.940 pc) |